Leaning vehicle suspension

Abstract

A suspension for a motorized rear wheel driven tricycle which can lean into turns includes a planar central upright frame which is mounted coaxially to the main frame of the tricycle. Upper and lower control arms are hinged to the central upright frame and extend to the left and to the right to connect to wheel bearing knuckles. An inverted rocker member is hinged to the central frame, pivotable about the front and rear ends of the central frame at about the midpoint between the top and bottom of the frame. The rocker member provides connection points for shock absorbers which interconnect the rocker member with each link member of the lower control arm on each side of the central frame. Drive members are supported on the central frame to continuously drive the rear wheels as the tricycle leans into turns.

1. A suspension for a motorized vehicle having a steerable front wheel, a pair of spaced apart rear wheels and an elongate frame supporting an engine, a transmission and a driver's seat, the invention comprising
 a central frame member longitudinally fixed to the elongate frame of the motorized vehicle, 
 the central frame member oriented substantially perpendicularly to a surface on which the motorized vehicle is supported when the suspension is in a non-leaning position, 
 the central frame member oriented at a substantial nonperpendicular to the surface on which the motorized vehicle is supported when the suspension is in a leaning position, 
 the central frame member having a left side and an opposing right side, 
 the central frame member further comprising a top edge and bottom edge, 
 a first upper control arm hinged at a proximal end thereof to the central frame member and extending from the left side thereof, 
 the first upper control arm hinged at a distal end thereof to a left wheel mounting assembly, 
 a second upper control arm hinged at a proximal end thereof to the central frame member and extending from the right side thereof, 
 the second upper control arm hinged at a distal end thereof to a right wheel mounting assembly, 
 a first lower control arm hinged at a proximal end thereof to the central frame member and extending from the left side thereof, 
 the first lower control arm hinged at a distal end thereof to a left wheel mounting assembly, 
 a second lower control arm hinged at a proximal end thereof to the central frame member and extending from the right side thereof, 
 the second lower control arm hinged at a distal end thereof to the right wheel mounting assembly, 
 the proximal ends of the first and second upper control arms defining a first axis aligned with a plane defined by the central frame member, 
 the proximal ends of the first and second lower control arms defining a second axis aligned with the plane defined by the central frame member, 
 the first upper control arm substantially parallel to the first lower control arm, 
 the second upper control arm substantially parallel to the second lower control arm, 
 the first upper control arm substantially coplanar with the second upper control arm, 
 the first lower control arm substantially coplanar with the second lower control arm, 
 a rocking member pivotally retained to the central frame member, 
 the rocking member disposed over the top edge of the central frame member when the suspension is in the non-leaning position, 
 the rocking member pivotal about an axis located between the top edge and a bottom edge of the central frame member, 
 the rocking member including a left side and an opposing right side, 
 at least one connection element extending from each of the left side and the opposing right side of the rocking member, 
 a first damping member interconnecting the at least one connection element extending from the left side of the rocking member to the first lower control arm, 
 a second damping member interconnecting the at least one connection element extending from the right side of the rocking member to the second lower control arm, 
 the pair of rear wheels comprises a left side wheel and a right side wheel, 
 the left side wheel mounted to the left side wheel mounting assembly, 
 the right side wheel mounted to the right side wheel mounting assembly, 
 each of the left side wheel and the right side wheel having a vertical centerline, 
 each of the distal ends of the first upper control arm and the first lower control arm defining a plane substantially coplanar with the vertical centerline of the left side wheel, 
 each of the distal ends of the second upper control arm and the second lower control arm defining a plane substantially coplanar with the vertical centerline of the right side wheel, 
 a drive member selectively driving the rear wheels, 
 the elongate frame of the vehicle leaning to the left when the suspension is in a left leaning position and the elongate frame of the vehicle leaning to the right when the suspension is in a right leaning position, 
 the rocking member pivoting to the right side of the central frame member when the suspension is in a left leaning position and the rocking member pivoting to the left side of the central frame member when the suspension is in a right leaning position. 
 
     
     
       2. The suspension for a motorized vehicle of  claim 1  wherein
 the first upper control arm comprises first and second left side upper rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second left side upper rod members spaced horizontally apart, 
 the second upper control arm comprises first and second right side upper rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second right side upper rod members spaced horizontally apart, 
 each of the first and second right side upper rod members including a distal end opposing the proximal end thereof, 
 the distal ends of each of the first and second right side upper rod members hinged to the right side wheel mounting assembly, 
 each of the first and second left side upper rod members including a distal end opposing the proximal end thereof, 
 the distal ends of each of the first and second left side upper rod members hinged to the left side wheel mounting assembly. 
 
     
     
       3. The suspension for a motorized vehicle of  claim 2  wherein
 the first lower control arm comprises first and second left side lower rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second left side lower rod members spaced horizontally apart, 
 the second upper control arm comprising first and second right side lower rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second right side lower rod members spaced horizontally apart, 
 each of the first and second right side lower rod members including a distal end opposing the proximal end thereof, 
 the distal ends of each of the first and second right side lower rod members hinged to the right side wheel mounting assembly, 
 the distal ends of each of the first and second left side lower rod members hinged to the left side wheel mounting assembly. 
 
     
     
       4. The suspension for a motorized vehicle of  claim 3  wherein
 the first and second left side upper rod members are joined by a cross bar, 
 the first and second right side upper rod members are joined by a cross bar, 
 the first and second left side lower rod members are joined by a cross bar, 
 the first and second right side lower rod members are joined by a cross bar. 
 
     
     
       5. The suspension for a motorized vehicle of  claim 1  wherein
 the first lower control arm comprises first and second left side lower rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second left side lower rod members spaced horizontally apart, 
 the second upper control arm comprises first and second right side lower rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second right side lower rod members spaced horizontally apart, 
 each of the first and second right side lower rod members including a distal end opposing the proximal end thereof, 
 the distal ends of each of the first and second right side lower rod members hinged to the right side wheel mounting assembly, 
 each of the first and second left side lower rod members including a distal end opposing the proximal end thereof, 
 the distal ends of each of the first and second left side lower rod members hinged to the left side wheel mounting assembly. 
 
     
     
       6. The suspension for a motorized vehicle of  claim 1  wherein
 the central frame member comprises a front edge and a rear edge, 
 the rocking member including a first pivot arm at a front end thereof and a second pivot arm at a rear end thereof, 
 the first pivot arm of the rocking member pivoting about a first pivot pin retained to the front edge of the central frame member, 
 the second pivot arm of the rocking member pivoting about a second pivot pin retained to the rear edge of the central frame member, 
 the first pivot pin coaxial with the second pivot pin. 
 
     
     
       7. The suspension for a motorized vehicle of  claim 6  wherein
 the first pivot pin and the second pivot pin are disposed approximately midway between the top edge and the bottom edge of the central frame member. 
 
     
     
       8. The suspension for a motorized vehicle of  claim 6  wherein
 the first pivot pin and the second pivot pin are disposed at approximately one-third of the distance between the top edge and the bottom edge of the central frame member. 
 
     
     
       9. The suspension for a motorized vehicle of  claim 1  wherein
 a differential is operatively connected to the left and right wheel mounting assemblies, 
 the differential mounted in a void in the central frame member. 
 
     
     
       10. The suspension for a motorized vehicle of  claim 1  wherein
 the first upper control arm comprises first and second left side upper rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second left side upper rod members spaced horizontally apart, 
 the second upper control arm comprises first and second right side upper rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second right side upper rod members spaced horizontally apart, 
 each of the first and second right side upper rod members including a distal end opposing the proximal end thereof, 
 the distal ends of each of the first and second right side upper rod members hinged to the right side wheel mounting assembly, 
 the distal ends of each of the first and second left side upper rod members hinged to the left side wheel mounting member, 
 the first lower control arm comprising first and second left side lower rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second left side lower rod members spaced horizontally apart, 
 the second upper control arm comprises first and second right side lower rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second right side lower rod members spaced horizontally apart, 
 each of the first and second right side lower rod members including a distal end opposing the proximal end thereof, 
 the distal ends of each of the first and second right side lower rod members hinged to the right side wheel mounting assembly, 
 the distal ends of each of the first and second left side lower rod members hinged to the left side wheel mounting assembly, 
 the first lower control arm comprising first and second left side lower rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second left side lower rod members spaced horizontally apart, 
 the second upper control arm comprising first and second right side lower rod members hinged at proximal ends thereof to the central frame member, 
 the proximal ends of the first and second right side lower rod members spaced horizontally apart, 
 each of the first and second right side lower rod members including a distal end opposing the proximal end thereof, 
 the distal ends of each of the first and second right side lower rod members hinged to the right side wheel mounting assembly, 
 the distal ends of each of the first and second left side lower rod members hinged to the left side wheel mounting assembly, 
 the first and second left side upper rod members joined by a cross bar, 
 the first and second right side upper rod members joined by a cross bar, 
 the first and second left side lower rod members joined by a cross bar, 
 the first and second right side lower rod members joined by a cross bar, 
 the central frame member further comprising a front edge and a rear edge, 
 the rocking member including a first pivot arm at a front end thereof and a second pivot arm at a rear end thereof, 
 the first pivot arm of the rocking member pivotable about a first pivot pin retained to the front edge of the central frame member, 
 the second pivot arm of the rocking member pivotable about a second pivot pin retained to the rear edge of the central frame member, 
 the first pivot pin coaxial with the second pivot pin, 
 the first pivot pin and the second pivot pin disposed between the top edge and the bottom edge of the central frame member, 
 the first pivot pin and the second pivot pin disposed approximately midway between the top edge and the bottom edge of the central frame member, 
 the first pivot pin and the second pivot pin disposed approximately one-third of the distance between the top edge and the bottom edge of the central frame member, 
 a differential is operatively connected to the left and right wheel mounting assemblies, 
 the differential mounted in an opening in the central frame member. 
 
     
     
       11. A suspension for a three-wheeled vehicle having a longitudinal main frame supported by a pair of spaced apart aligned wheels and a third steerable wheel, the invention comprising
 a central frame removably fixed to the main frame of the vehicle, 
 a plurality of elongate arms pivotally retained to the central frame, the plurality of elongate arms each including a proximal end hinged to the central frame, 
 the plurality of elongate arms including:
 a first upper elongate arm extending from the central frame to a mounting for a left wheel of the pair of wheels, 
 a second upper elongate arm extending from the central frame to a mounting for a right wheel of the pair of wheels, 
 a first lower elongate arm extending from the central frame to the mounting for the left wheel of the pair of wheels, 
 a second lower elongate arm extending from the central frame to the mounting for the right wheel of the pair of wheels, 
 
 a proximal end of the first upper elongate arm horizontally aligned with a proximal end of the second upper elongate arm and spaced apart therefrom, 
 a proximal end of the first lower elongate arm horizontally aligned with a proximal end of the second lower elongate arm and spaced apart therefrom, 
 the proximal ends of the first and second upper elongate arms retained to the central frame above the proximal ends of the first and second lower elongate arms, 
 the first upper elongate arm substantially horizontally aligned with the second upper elongate arm, 
 the first lower elongate arm substantially horizontally aligned with the second lower elongate arm, 
 a distal end of the first upper elongate arm and a distal end of the first lower elongate arm each pivotally retained to the mounting for the left wheel, 
 a distal end of the second upper elongate arm and a distal end of the second lower elongate arm each pivotally retained to the mounting for the right wheel, 
 a rocking member overlying the central frame and separated therefrom by a small distance, 
 the rocking member pivotally retained to the central frame between a top and a bottom of the central frame, 
 the rocking member including at least one mounting on each of a left side and a right side thereof, 
 at least one shock absorbing member interconnecting the at least one mounting on the left side of the rocking member with the first lower elongate arm, 
 at least one shock absorbing member interconnecting the at least one mounting on the right side of the rocking member with the second lower elongate arm, 
 the central frame leaning toward a left side of the vehicle when the vehicle is steered to the left and the central frame leaning toward a right side of the vehicle when the vehicle is steered to the right, 
 the rocking member moving toward the right wheel when the central frame leans toward the left side of the vehicle and the rocking member moving toward the left wheel when the central frame leans toward the right side of the vehicle. 
 
     
     
       12. The suspension of  claim 11  wherein
 each elongate arm comprises a pair of spaced apart elongate links, 
 each link including a distal end, 
 the distal ends of the links of the first upper elongate arm hinged to the mounting for the left wheel, 
 the distal ends of the links of the second upper elongate arm hinged to the mounting for the right wheel, 
 the distal ends of the links of the first lower elongate arm hinged to the mounting for the right wheel, 
 the distal ends of the links of the second lower elongate arm hinged to the mounting for the right wheel, 
 each link including a proximal end, 
 the proximal ends of the links of the first upper elongate arm hinged to the central frame, 
 the proximal ends of the links of the second upper elongate arm hinged to the central frame, 
 the proximal ends of the links of the first lower elongate arm hinged to the central frame, 
 the proximal ends of the links of the second lower elongate arm hinged to the central frame. 
 
     
     
       13. A suspension for a vehicle comprising
 a central frame defining a plane, 
 the plane generally upright when the suspension is in a non-leaning position, 
 the central frame leaning to the left when the suspension is in a left leaning position, 
 the central frame leaning to the right when the suspension is in a right leaning position, 
 the central frame having a left side and an opposing right side, 
 the central frame further having a top and a bottom and a front edge and rear edge, 
 a first upper control arm extending from the left side of the central frame to a mounting for a left wheel, 
 a second upper control arm extending from the right side of the central frame to a mounting for a right wheel, 
 a first lower control arm extending from the left side of the central frame to the mounting for the left wheel, 
 a second lower control arm extending from the right side of the central frame to the mounting for the right wheel, 
 each control arm pivotally retained at a proximal end thereof to the central frame, 
 each control al n pivotal about an axis coplanar with the plane defined by the central frame, 
 the proximal end of the first upper control arm horizontally aligned with the proximal end of the second upper control arm and spaced apart therefrom, 
 the proximal end of the first lower control arm horizontally aligned with the proximal end of the second lower control arm and spaced apart therefrom, 
 the first upper control arm substantially horizontally aligned with the second upper control arm, 
 the first lower control arm substantially horizontally aligned with the second lower control arm, 
 a distal end of the first upper control arm and a distal end of the first lower control arm each pivotally retained to the mounting for the left wheel, 
 a distal end of the second upper control arm and a distal end of the second lower control arm each pivotally retained to the mounting for the right wheel, 
 a rocking member overlying the central frame and separated from the top of the central frame by a small distance when the central frame is substantially upright, 
 the rocking member pivotally retained to the central frame, 
 the rocking member pivotal about an axis located between the top and the bottom of the central frame, 
 the rocking member including at least one mounting element on each of a left side and a right side thereof, 
 at least a first damping member interconnecting the at least one mounting element on the left side of the rocking member with the first lower control arm, 
 at least a second damping member interconnecting the at least one mounting element on the right side of the rocking member with the second lower control arm, 
 the rocking member moving toward a right side of the central frame when the central frame leans to the left and the rocking member moving toward the left side of the central frame when the central frame leans toward the right. 
 
     
     
       14. The suspension of  claim 13  wherein
 the axis of pivot of the rocking member is located in an upper one-half of the central frame. 
 
     
     
       15. The suspension of  claim 13  wherein
 the axis of pivot of the rocking member is located in an upper one-third of the central frame. 
 
     
     
       16. The suspension of  claim 13  wherein
 each control arm comprises a pair of tie rods, 
 each tie rod of the pair of tie rods of each of the control arms is a mirror image of the other tie rod of the pair of tie rods, 
 each tie rod includes a proximal end pivotally retained to the central frame, 
 each tie rod includes a distal end pivotally retained to a wheel mounting member, 
 each proximal end of each tie rod of the first upper control arm is offset laterally from each proximal end of each tie rod of the second upper control arm, 
 each tie rod of the first upper control arm is coplanar with each tie rod of the second upper control arm, 
 each lower control arm is parallel to each upper control arm. 
 
     
     
       17. The suspension of  claim 13  wherein
 the rocking member includes a pair of pivot arms, 
 a first of the pivot arms retained to a first pivot pin on a the front edge of the central frame, 
 a second of the pivot aims retained to a second pivot pin on a the rear edge of the central frame, 
 the first pivot pin coaxial with the second pivot pin, 
 the first pivot pin and the second pivot pin located upon an upper one-half of the central frame. 
 
     
     
       18. The suspension of  claim 13  wherein
 the rocking member comprises a beam, 
 the at least one mounting element on each side of the rocking member comprising an arm extending from the beam. 
 
     
     
       19. The suspension of  claim 13  wherein
 the mounting for the left wheel is a left wheel bearing housing, 
 the mounting for the right wheel is a right wheel bearing housing. 
 
     
     
       20. The suspension of  claim 13  wherein
 the rocking member comprises a longitudinal beam, 
 the longitudinal beam including at least one cross member transverse to the longitudinal beam, 
 the at least one cross member having opposing ends, 
 a pivot arm depending from each of the opposing ends of the at least one cross member, 
 a first of the pivot anus hinged to a first pivot connection fixed to the right side of the central frame, 
 a second of the pivot arms hinged to a second pivot connection fixed to the left side of the central frame.